Locking mechanism for safe and other secure storage apparatus

Abstract

A locking mechanism suitable for use with a door or other entry point is contemplated. The locking mechanism may include cams, levers or other features operable to facilitate securing the door against prying, wedging and related techniques intended to compromise secure by physically separating the door from a door frame or other support structure.

What is claimed is: 
     
       1. A safe comprising:
 a housing including a plurality of walls arranged to provide a secure storage area, the plurality of walls including a first sidewall, a second sidewall, a top wall, a bottom wall and a front wall, wherein the first sidewall is horizontally spaced apart from the second sidewall and the top wall is vertically spaced apart from the bottom wall, wherein the front wall includes an opening to the secure storage area and is proximate forward ends of the first sidewall, the second sidewall, the top wall and the bottom wall; 
 a door attached with a hinge to the front wall, the door being movable about the hinge between an opened position and a closed position, the opened position positioning the door away from the front wall to permit access to the secure storage area, the closed position positioning the door in alignment with the front wall to prevent access to the secure storage area; 
 a locking mechanism attached to the door, the locking mechanism including: 
 i) a first cam operable between an engaged position and a disengaged position, wherein a first hook included on the first cam is shaped to be positioned within a first recess included in the first sidewall such that at least a portion of the first hook overlaps at least a portion of a perimeter of the first recess when the first cam is in the engaged position while the door is in the closed position, wherein the first hook is shaped to be positioned away from the first recess such that no portion of the first hook overlaps the portion of the perimeter of the first recess when the first cam is in the disengaged position while the door is in the closed position; and 
 ii) a lock operable between a locked position and an unlocked position, the locked position preventing movement of the first cam from the engaged position to the disengaged position, the unlocked position permitting movement of the first cam from the engaged position to the disengaged position, thereby securing access to the secure storage area when the door is in the closed position, the first cam is in the engaged position and the lock is in the locked position; 
 wherein the locking mechanism includes a second cam operable between the engaged position and the disengaged position, wherein a second hook included on the second cam is shaped to be positioned within a second recess included in the first sidewall such that at least a portion of the second hook overlaps at least a portion of a perimeter of the second recess when the second cam is in the engaged position while the door is in the closed position, wherein the second hook is shaped to be positioned away from the second recess such that no portion of the second hook overlaps the portion of the perimeter of the second recess when the second cam is in the disengaged position while the door is in the closed position; 
 wherein the locking mechanism includes a linkage for mechanically coupling the first cam with the second cam such that the first cam moves in concert with the second cam between the engaged position and the disengaged position; and 
 wherein the second cam includes a foot, wherein the foot is shaped: 
 i) such that the foot extends behind or into a portion of the front wall when the second cam is in the engaged position while the door is in the closed position; and 
 ii) such that no portion of the foot extends behind or into the front wall when the second cam is in the disengaged position while the door is in the closed position. 
 
     
     
       2. The safe of  claim 1  wherein the locking mechanism includes a handle mechanically coupled with the linkage such that rotation of the handle moves the linkage between a first position and a second position, the first position being sufficient to actuate the first cam and the second cam in concert to the engaged position and the second position being sufficient to actuate the first cam and the second cam in concert to the disengaged position. 
     
     
       3. The safe of  claim 2  wherein:
 the lock includes a bolt, the bolt being fixed in an extended position when the lock is in the locked position and being operable to a retracted position when the lock is in the unlocked position; and 
 the first cam includes a ledge shaped to engage the bolt when the first cam is in the engaged position while the lock is in the locked position, thereby preventing the linkage from moving in response to rotation of the handle. 
 
     
     
       4. The safe of  claim 3  wherein the ledge engages the bolt when the first cam is in the engaged position while the lock is in the unlocked position such that subsequent rotation of the handle moves the linkage that in turn moves the first cam and thereby the ledge against the bolt whereupon the bolt begins to move from the extended position to the retracted position. 
     
     
       5. The safe of  claim 2  wherein the locking mechanism includes:
 a handle spring for biasing the linkage toward the first position when rotation of the handle moves the linkage toward the second position; and 
 an auto-detent mechanism for retaining the linkage in the second position against the handle spring biasing, the auto-detent mechanism including a pin journaled within a channel of the first cam and a pin spring for biasing the pin against a rearward surface of the channel such that the pin automatically engages a notch at a distal end of the channel in a manner sufficient to retain the linkage in the second position against the handle spring biasing. 
 
     
     
       6. The safe of  claim 5  wherein the auto detent mechanism includes a push rod attached to the pin that pushes the pin out of the notch when the door is moved from the opened position to the closed position while the cam is in the disengaged position, thereby permitting the handle spring biasing to automatically move the linkage from the second position to the first position and return the cam to the engaged position. 
     
     
       7. The safe of  claim 1  wherein the first cam includes a foot, wherein the foot is shaped:
 such that the foot extends behind or into a portion of the front wall when the first cam is in the engaged position while the door is in the closed position; and 
 such that no portion of the foot extends behind or into the front wall when the cam is in the disengaged position while the door is in the closed position. 
 
     
     
       8. A locking mechanism for securing a door when mounted to a door frame, the door frame including a door jamb between a door header and a door sill and the door being operable therein between an opened position and a closed position, the locking mechanism comprising:
 a first cam operable between an engaged position and a disengaged position, wherein the first cam includes a first hook shaped to: 
 i) to overlap a back side of the door jamb via a first opening included therein when the first cam is in the engaged position while the door is in the closed position, the back side of the door jamb being opposite to a front side of the door jamb interfacing with the door; and 
 ii) disengage from the first opening when the first cam is in the disengaged position while the door is in the closed position; 
 a second cam operable between the engaged position and the disengaged position, wherein the second cam includes a second hook shaped to: 
 i) to overlap the back side of the door jamb via a second opening included therein when the second cam is in the engaged position while the door is in the closed position; and 
 ii) disengage from the second opening when the second cam is in the disengaged position while the door is in the closed position; 
 a linkage for mechanically coupling the first cam with the second cam such that the first cam moves in concert with the second cam between the engaged position and the disengaged position; 
 a handle mechanically coupled with the linkage such that movement of the handle induces corresponding movement in the linkage, and thereby, the first and second cams, wherein the handle is configured to permit movement sufficient to operate the first and second cams from the engaged position to the disengaged position; and 
 wherein the second cam includes a foot, wherein the foot is shaped: 
 i) such that the foot extends behind a portion of the door sill or within a door sill recess included therein when the second cam is in the engaged position while the door is in the closed position; and 
 ii) such that no portion of the foot extends behind or within the door sill when the second cam is in the disengaged position while the door is in the closed position. 
 
     
     
       9. The locking mechanism of  claim 8  further comprising:
 a first pivot for pivotally attaching the first cam relative to the door; 
 a second pivot for pivotally attaching the second cam relative to the door; and 
 wherein the linkage simultaneously rotates the first and second cams about the first and second pivots when moving from the engaged position to the disengaged position in response to corresponding movement of the handle. 
 
     
     
       10. The locking mechanism  claim 9  wherein:
 the first hook is shaped to provide a first relief sufficient to permit the first cam to rotate into the first opening when moving from the disengaged position to the engaged position such that substantially an entire length of the first relief is positioned below the first opening when the engaged position is reached; and 
 the second hook is shaped to provide a second relief sufficient to permit the second cam to rotate into the second opening when moving from the disengaged position to the engaged position such that substantially an entire length of the second relief is positioned below the second opening when the engaged position is reached. 
 
     
     
       11. The locking mechanism of  claim 10  further comprising a lock operable between an unlocked position and a locked position, the lock including a bolt positioned relative to at least one of the first and second cams, the linkage and the handle such that the bolt blocks rotation of the first and second cams from the engaged position to the disengaged position when the lock is in the locked position and such that the bolt does not block rotation of the first and second cams from the engaged position to the disengaged position when the lock is in the unlocked position. 
     
     
       12. The locking mechanism of  claim 11  wherein:
 the lock is positioned relative to the first cam; and 
 the first cam includes a ledge shaped to engage the bolt, the shape being sufficient for preventing movement of the first cam to the disengaged position when the first cam is in the engaged position while the lock is in the locked position. 
 
     
     
       13. The locking mechanism of  claim 12  wherein the door frame is included as part of a safe configured for securing a cassette within a secure storage area accessible through the door. 
     
     
       14. A safe comprising:
 a housing including a plurality of walls arranged to provide a secure storage area, the plurality of walls including a first sidewall, a second sidewall, a top wall, a bottom wall and a front wall, wherein the first sidewall is horizontally spaced apart from the second sidewall and the top wall is vertically spaced apart from the bottom wall, wherein the front wall includes an opening to the secure storage area and is proximate forward ends of the first sidewall, the second sidewall, the top wall and the bottom wall; 
 a door attached with a hinge to the front wall, the door being movable about the hinge between an opened position and a closed position, the opened position positioning the door away from the front wall to permit access to the secure storage area, the closed position positioning the door in alignment with the front wall to prevent access to the secure storage area; and 
 a locking mechanism attached to the door, the locking mechanism including: 
 i) a first cam operable between an engaged position and a disengaged position, wherein a first hook included on the first cam is shaped to be positioned within a first recess included in the first sidewall such that at least a portion of the first hook overlaps at least a portion of a perimeter of the first recess when the first cam is in the engaged position while the door is in the closed position, wherein the first hook is shaped to be positioned away from the first recess such that no portion of the first hook overlaps the portion of the perimeter of the first recess when the first cam is in the disengaged position while the door is in the closed position; and 
 ii) a lock operable between a locked position and an unlocked position, the locked position preventing movement of the first cam from the engaged position to the disengaged position, the unlocked position permitting movement of the first cam from the engaged position to the disengaged position, thereby securing access to the secure storage area when the door is in the closed position, the first cam is in the engaged position and the lock is in the locked position 
 wherein the locking mechanism includes a second cam operable between the engaged position and the disengaged position, wherein a second hook included on the second cam is shaped to be positioned within a second recess included in the first sidewall such that at least a portion of the second hook overlaps at least a portion of a perimeter of the second recess when the second cam is in the engaged position while the door is in the closed position, wherein the second hook is shaped to be positioned away from the second recess such that no portion of the second hook overlaps the portion of the perimeter of the second recess when the second cam is in the disengaged position while the door is in the closed position; 
 wherein the locking mechanism includes a linkage for mechanically coupling the first cam with the second cam such that the first cam moves in concert with the second cam between the engaged position and the disengaged position; 
 wherein the locking mechanism includes a handle mechanically coupled with the linkage such that rotation of the handle moves the linkage between a first position and a second position, the first position being sufficient to actuate the first cam and the second cam in concert to the engaged position and the second position being sufficient to actuate the first cam and the second cam in concert to the disengaged position; and 
 wherein the locking mechanism includes: 
 i) a handle spring for biasing the linkage toward the first position when rotation of the handle moves the linkage toward the second position; and 
 ii) an auto-detent mechanism for retaining the linkage in the second position against the handle spring biasing, the auto-detent mechanism including a pin journaled within a channel of the first cam and a pin spring for biasing the pin against a rearward surface of the channel such that the pin automatically engages a notch at a distal end of the channel in a manner sufficient to retain the linkage in the second position against the handle spring biasing. 
 
     
     
       15. The safe of  claim 14  wherein:
 the lock includes a bolt, the bolt being fixed in an extended position when the lock is in the locked position and being operable to a retracted position when the lock is in the unlocked position; and 
 the first cam includes a ledge shaped to engage the bolt when the first cam is in the engaged position while the lock is in the locked position, thereby preventing the linkage from moving in response to rotation of the handle. 
 
     
     
       16. The safe of  claim 15  wherein the ledge engages the bolt when the first cam is in the engaged position while the lock is in the unlocked position such that subsequent rotation of the handle moves the linkage that in turn moves the first cam and thereby the ledge against the bolt whereupon the bolt begins to move from the extended position to the retracted position. 
     
     
       17. The safe of  claim 14  wherein the auto detent mechanism includes a push rod attached to the pin that pushes the pin out of the notch when the door is moved from the opened position to the closed position while the cam is in the disengaged position, thereby permitting the handle spring biasing to automatically move the linkage from the second position to the first position and return the cam to the engaged position. 
     
     
       18. The safe of  claim 14  wherein the first cam includes a foot,
 wherein the foot is shaped: 
 such that the foot extends behind or into a portion of the front wall when the first cam is in the engaged position while the door is in the closed position; and 
 such that no portion of the foot extends behind or into the front wall when the cam is in the disengaged position while the door is in the closed position.